/Engine/Plugins/Runtime/RigVM/Source/RigVM/Public/RigVMCore/RigVM.h
Adds a new external / unowned variable to the VM.
[FRigVMOperand](API\Plugins\RigVM\RigVMCore\FRigVMOperand) AddExternalVariable ( [FRigVMExtendedExecuteContext](API\Plugins\RigVM\RigVMCore\FRigVMExtendedExecuteContext) & Context, const [FRigVMExternalVariable](API\Plugins\RigVM\RigVMCore\FRigVMExternalVariable) & InExternalVariable, bool bAllowNullMemory )